| Abstract: | ABSTRACT Procedures used to establish current and prospective manufacturing water withdrawals in a river basin are described. The needs study incorporated a computerized analysis of industrial requirements at basin, county and county subarea levels. Current usage in the universe of industries was examined preparatory to the determination of probable future withdrawals, to facilitate plan formulation with constraints involving large masses of data. In preparing the needs estimates, it was assumed that employment data on an establishment basis would provide a reasonably current, consistent and continuing basis for relating the water demands of an industry to the operating rate of its establishments, when changes in employment were related to the trend in output per employee, and intake per employee was related to water use technology by analysis of reuse, and use by function. The forecasting technique described employs a well-defined data base, accounts for the major share of self-supplied needs generally disregarded in per-capita demand estimates, and differentiates between the “once-through” and recycled components of initial withdrawal. |
